Furnace



(No Model.) 4 Y K; lVI. JARVIS.

FURNAGB.

No. 302,848. Patented July 29, 1884..

N. Pneus. Phowumagnpner, miningm n4 c.

raten@ -KINGSBURY M. JARVIS, OF MALDEN, ASSIGNOR TO JARVIS ENGINEERINGCOMPANY, F BOSTON, MASSACHUSETTS.

FURNACE.

SPECIFICATION forming part of Letters Patent No. 302,848, dated J'Yuly29, 1884.

Application tiled March 15, 1883.

To all whom, it may concern:

Be it known that I, KiNGsBURY M. JARvIs, of Malden,county of Middlesex,State of Massachusetts, have invented an Improvement in Furnaces, ofwhich the following description,

in connection with the accompanying drawings, is aspecication,likeletters on the drawings representing like parts.

My invention, relating to furnaces, has forits IO object to control theadmission of air or oxygen to combine with the fuel, and also to controlthe passage for the escape of the products of combustion to the uptakeor chimney, so that the said escape or outlet of the furnace will alwaysbe proportional to the amount of air admitted, and the furnace will thusalways work freely, and the fire will be completely under control of theattendant.

The invention is shown embodied in a fur- 2O nace substantially such asdescribed in Letters Patent No. 222,681, granted to me December 16,1879, in wich the walls of the furnace are provided with air-heatingpassages, through which the air is admitted tothe combustionchambersabove the fuel on the grate, the said `air thus being heated to4 a hightemperature, and combining readily with the partiallyconsumed gases andsmoke arising from the fuel and producing perfect combustion. In my for-O mer furnaces the air thus admitted and heated in its passage throughthe Walls has simply been drawn in bythe natural draft of the furnace,the said passages having as their inlet merely openings to theatmosphere. In my present inyention the said heatingpassages areconnected with an air-forcing apparatus, shown in this instance as a fanoperated by steam in any suitable or usual manner, and the said forcingapparatus and the damper in 4o the iiue or passage to the stack havecontrolling mechanism common to them both,whereby the said damper isopened and a freer exit is afforded to the products of combustion inproportion to the increase in amount of air admit- 4 5 ted or introducedby the forcing apparatus.

Figure l is afront elevation ofafurnace embodying" this invention, andFig. 2 a side elevation thereof.

rlhe furnaceAmay be substantially the same 5o as in Letters Patent Nos.17 6,633, 186,734,

189,862, or 222,631, it being provided with one (No model.)

`or more ai r-heating passages or ducts, a b, ,in its walls, throughwhich air circulates, and from which it is admitted to thecombustionchamber of the furnace at a high temperature. 5 5 In thepresent invention the said ducts a b are connected with passages c,shown as formed in the front walls of the furnace, and themselvesconnected with pipes d, branchingI from an airforcingapparatus,consistingin this instance of 6o a fan-blower, e, of anyusualor suitable construction, actuated bysteam from the steam-pipef. Theflow of steam through the pipef, and the consequent speed of the blowerand amount of air carried into the pipes d and ducts a b, is

.controlled by a cock or valve, t', which thus,

constitutes a draft controlling device, and is operated by a rod orlink, m, connected with the actuating-arm n of the damper o in thecscape-fiue fr of the furnace, by which the escape 7o of the products ofcombustion is controlled. rlhe said damper o and cock i are thuscausedto operate in unison, and are so arranged that they are bothopened and closed together, thus increasing or decreasing the passagefor the escape of the products of combustion from the furnace inproportion as the amount of air admitted is increased or decreased. Thedamper and cock are operated by a suitable handle or rod, t, connectedwith the arm n., so 8o that the attendant, by a single movement,operates both the damper and the cock by which the introduction of airis controlled.

The invention is not limited to the particular form of apparatus shown,as it is obvious that the air might be forced by other apparatus th anthe fanbloWer, and that the amount of air admitted to the furnace mightbe controlled by a valve or gate in the pipe leading to the pipe A d,the essential feature of the invention being 9o that the ad mission ofair and outlet for the products of combustion are controlled in unison,so that they always have the pr'oper relation to one another to insurethe proper operation of the furnace. Anovel fairblower especially 9 5adapted for this use will form the subject of another application forLetters Patent.

Vhen the present invention is to be applied to furnaces alreadyconstructed in accordance with the improvements referred to, the pipesroov d might pass down the outside of the Walls of the/furnace to theoriginal inlet-opening of the ducts ab. An inlet-opening is preferablyprocombined with the outlet-flue or uptake and vided in the front Wallof the furnace, as at u, it being provided with .a covering-platemhichmay be removed if it is desired to Work the furnace by natural draftonly, or in case the air-forein g apparatus becomes temporarilydisabled.

I Claiml. In a furnace, the smokeue and damper therein, air-ductslleading to the ire and separate from said smoke-iiue, and anair-forcing apparatus for said ducts, combined with mechanism forcontrolling the air-forcing apparatus and the damper in the smoke flueor stack' common to both, whereby the exit in the smoke-flue is properlyproportioned to the admission of air to the fire, substantially asdescribed.

2. The heating-duets in the walls oi" a 'l'urnace, and fan-blower forforcing air into them, and a cock or valve controlling` its operation,

damper therein, and actuating mechanism common to the said damper andcontrolling cock or valve for the fan-blower, substantially 2 5 as andfor the purposes set forth. f

3. In a furnace, the heated air-ducts c and an air-forcing apparatus forsaid ducts, com-- bined with the cock or valve i, for controlling theoperating medium of the air-forcingap- 3o paratus, and the damper o inthe smoke-flue, botli the valve fi and damper o operable by mechanismcommon to both, substantially as described.

In testimonywhereoflhave signed my name 35 to this specification in thepresence of two subscribing Witnesses.

KINGSBURY M. JARVIS.

Nifitnesses:

G. W. GREGORY, W. H. SIGsToN.

